Roaming Won’t Come Easy in the Global Village

The next generation of roaming will bring with it issues around real-time clearing of roaming records, inter-standard cooperation, revenue assurance and QoS.

More than 650 million wireless subscribers roam the planet, and 56 percent of them use GSM phones. While the United States still hangs on to TDMA and CDMA, it, too, is preparing to support GSM as a global footprint, as evidenced by AT&T’s alliance with NTT DoCoMo. “In moving to the GSM standard, AT&T will have potential roaming capabilities with more than 80 percent of the global market,” says Jordan Roderick, president of AT&T Wireless’ international roaming division.

For subscribers, the predominance of GSM means low-price handsets and international roaming capabilities. For international operators, however, GSM can mean roaming and billing headaches, as there are still many unresolved issues concerning the supply of GPRS handsets; inter-standard roaming for voice and eventually non-voice calls, revenue assurance and quality of service (QoS).

Testing the Waters

Handset manufacturers are holding off, rather than produce millions of devices that might suddenly become obsolete because of changing standards. GPRS handsets are supplied by only a few manufacturers—none of which supply them in high volume. The handsets produced today by manufacturers like Nokia, Ericsson or Motorola are only 2/1 or 3/1, meaning users can use two or three channels downstream and one channel upstream. What’s more, the bandwidths offered by these handsets are quite far off from the promised maximum of 115 Kbps.

It seems as though the GSM industry is waiting to see how customers will embrace GPRS, and the operators are struggling to find captivating software and the best way to price their services, wither by data volume or by minutes.

“While nobody knows what the killer application will be, we know that the first natural benefit of GPRS will be access to corporate LANs and e-mail when roaming,” says Sue Campion, manager of mobile carrier services for Cable and Wireless Communications in the United Kingdom. CW offers a range of services, including voice traffic, provisioning of data networks internationally and mobile Internet applications through a partnership with Nokia. Users have access to e-mail on their corporate servers and can work on files from their mobile phones.

“Beyond that, the whole realm of wireless applications could go in any direction,” Campion says. CW’s development team is working on a GPRS roaming network that it expects will enable mobile operators to connect and exchange traffic with any mobile operator when customers are roaming. “We have parts of the solution out there through our network, and we are trying to build a scalable solution that meets all of the GSM Alliance requirements.”

The company also was recently certified by the North American portion of the GSM Alliance to provision GRX (GPRS roaming exchange services. GRX is considered an area to be watched closely for roaming with GPRS. “We see GRX offering a variety of services, such as access to home networks when roaming,” says Campion (see “Defining QoS,” below).

Technology Gaps in Inter-standard Roaming

Whether based on GSM or IS.41, at issue will be how to accommodate multifarious billing formats and standards within those formats among roaming partners. With more than 350 roaming operators using different transfer account protocol (TAP) file formats, validation and conversion will become a daunting process under international roaming agreements.

Most files exchanged today between roaming partners are TAP transactions. That won’t change anytime soon, because the GSM Association mandates that all public traffic among operators be TAP3 files. TAP3 is the format for present and future services, in which data about roamers from a particular operator is collected and sent via EDI. As operators move into the data world with TAP3, which is GPRS-compliant, they will have to keep up with two new releases every year—one minor and one major. That means operators will have to update and adjust their systems accordingly. This will be difficult, because most of today’s billing systems are not prepared to handle all the information necessary to build a TAP3 file. Only a few billing vendors comply with updates to the standard or have released it on schedule.

GTE-TSI, which now falls under Verizon Data Services, is one of the few vendors to offer inter-standard roaming and billing between GSM and IS.41, through its Global Roam product.

Conversion

Where earlier TAP formats were ASCII-based, and consequently much easier to edit/view, it will now be quite costly to make changes to a complex billing system. Operators can lose information encoded in the higher-level TAP files when converting to a lower format. For that reason, it is expected most operators will look to trusted third parties and clearinghouses to handle the conversion process (see “Clearinghouses Will Play a Bigger Role,” below)

“If an operator chooses to stay on TAP1, in most cases because their billing systems do not support the newer formats, then we must prepare to read the file and convert it to TAP2, TAP2+ or TAP3,” says Jesper Andersen, product manager for Dan Net A/S in Denmark. Converting TAP files poses no major problems for now. However, Andersen says, “You are bound to lose information specific for TAP3 when converting to TAP1.” The reason is that lower TAP formats are restricted to contain only certain kinds of information. Because TAP3 is encoded in the ASN.1 format, it is not readable from a text editor. That makes it difficult to build perfect TAP3 files. Andersen says that Dan Net customers often choose to outsource the building of TAP files altogether. Dan Net offers an outsourcing service called TFG.

“It is often a question of server capacity for the operator,” says Andersen. As GSM operators will somehow have to connect with multiple content providers to collect key data—including call information, and tariff and roaming charges—the challenge will be to retrieve data from the network and get it to the billing system.

“Operators will have to figure out a way to collect data and translate it into a format their billing system will understand,” says Pat Walls of GTE’s architecture and technology group. To do so, and in a timely manner, is much more difficult than it sounds.

Clearinghouses Will Play Bigger Role

As a result, it is expected most operators will end up looking to the clearinghouses and trusted third parties for re-rating services, generating TAP files and delivering bills; otherwise, it will be up to operators to keep abreast of standards and to have dedicated circuits in place.

There are a handful of international data clearinghouses, including MACH in Luxembourg, EDS in Germany, Etisalat in the UAE, Comfone in Switzerland, and GTE in the United States.

These clearinghouses offer a variety of validation services for both sending and receiving. Operators can send files with or without the use of any value-adding service. Clearinghouses typically check for tariff, tax, duplicate records and old records, as well as validate the structure of the files and ensure that basic syntax rules are followed.

Some operators prefer the one-to-one connection method, such as Vodafone in the United Kingdom, China Telecom, Panafon of Greece and Telefonica of Spain.

Most operators, however, won’t be able to abide by delivery times in international roaming. There already are major problems in terms of real-time access to customer records. In some markets, customer queries about roaming aren’t answered for two or three months. This can be detrimental, since in many markets customers aren’t responsible for payment of bills not received within a month or so. “Operators increasingly will pay to clear their records, but as it is now, those records are cleared slowly, so they are not collecting revenue as quickly as they could,” says DMR Consulting’s Nick Lazario, who believes controls are needed between carriers. While the agreements are in place, he believes the technology and the process to make it happen effectively are not.

“The prepaid solutions worldwide are able to work real-time in order to count down the accounts of the subscribers, so it’s not a matter of not having the technical wherewithal,” Lazario says.

Real-time?

New billing systems or enhancements of existing billing systems will have to cope with real-time and event-based billing. That is difficult enough by itself, and wireless data introduces a new dimension of difficulty in clearing for mediation and billing vendors. Unlike traditional voice models, where there existed operator-to-operator clearing, non-voice roaming will involve third parties, as content providers and portals are entered into the equation.

“You can think of it as virtual roaming,” says Dave Estes, group product manager in GTE’s clearinghouse. “When you think of the voice model today, there are wireless operators along the network, but in the IP space you will have subscribers jumping off the network into areas that operators can no longer see. Even if an operator knows that a customer is going to request something on the Internet, there is no visibility of what specifically.”

As a result, there will have to be some type of agreement in place among operators, content providers and portals on the other side of the Internet. “The agreement could be, ‘If my customer buys a book, then I want a commission for enabling him to do that,’ ” Estes says.

Some foresee direct mobile payment for goods. “Perhaps a customer will have two accounts on one SIM card, thereby enabling the customer to pay for goods directly when ordering over a mobile phone—actually acting as a prepaid subscriber and as post-paid subscriber for traditional voice, fax and data calls,” says Michael Dickerson, director of global sales for Dan Net. “Every transaction, even the goods already being paid for, will be listed on the bill.”

For such applications to be possible, real-time data clearing must be addressed. Standards are emerging to answer issues of timeliness.

Age edits

Under Cyber, an “age edit” requires that servicing carriers submit records and process and rate calls to clearinghouses within 30 days; otherwise, the records are sent back and the operator loses the revenue. However, switch problems and upgrades continue to cause some problems in exchanging records, delaying the process two to three months.

“Participation with Cyber hasn’t taken off, as TAP billing is still perceived to have advantages over Cyber,” says GTE’s Walls. The TAP record is a little ahead in supporting data, she believes, whereas Cyber is just now being modified to support SMS and IP initiatives. “TAP is more aggressive on that end.”

Indeed, developments are being made with TAP. By April 1, a new service called “Rejects and Returns” will be mandatory on public interfaces. “This will automatically remove erroneous records from the TAP file and return them in a ‘RAP’ field to the sender. The senders will then acknowledge that with an ‘ACK’ file,” says Dan Net’s Andersen. “Using this new method of exchanging files, the correct data gets to the roaming partner almost instantly, and the sender has the possibility of correcting the records in the RAP file for later resubmission.”

Revenue Assurance

Other than adjusting business models for more event-based and timely billing, operators will also have to focus on maximizing revenue.

“Some operators have not yet acknowledged the importance of the revenue that stems from roaming,” says Andersen, who believes the consolidation of operators claiming to be pan-European will affect pricing strategies. “Operators will be able to see an increase of profit, when the price plans for roaming calls are based on valid data and behavior analysis, rather than from the traditional mark-up principle,” he says. “When thinking about decreasing revenue in the domestic market from the operator, the revenue stream from roaming calls is vital.”

As a result, operators will want to analyze customer roaming behavior. So, in addition to conversion and billing, clearinghouses will see a surge in demand for data mining and data warehouse services as well.

Dan Net already offers a product called Data Mart, a tool for analyzing national traffic for operators whose billing systems don’t offer that functionality.

Defining QoS

As operators collect more pertinent data about roaming behavior, they will figure out how to bill appropriately for roaming. “As ISPs move up the value chain, offering value-added service such as lower delay, there also will have to be protocols that enable QoS differentiation on an Internet backbone,” says Iain Stevenson, a consultant with Ovum Ltd., in London.

No one is really doing that, “because no one yet understands how to differentiate QoS across boundaries,” Stevenson says. He believes user pressure will grow, causing carriers to partner with local providers over the next three to five years.

“The important thing is to offer the customer the same level of service when roaming in foreign networks, both for QoS and pricing,” says John Hoffman, who leads the GPRS initiative within the GSM Alliance. However, consistency in service and pricing is difficult. Ovum’s Stevenson sees “ a very patchy picture,” as carriers vie to become the most dominant player with their fiber backbones. As a result, there are countries with no networks, so operators go back to roaming or fixed roaming through local ISPs, as some carriers don’t want to partner with local providers. “Eventually they will have to realize they can’t all be pioneers, and they will realize partnerships with local providers will be necessary,” Stevenson says.

Consequently, guaranteeing the SLA will be difficult in IP, when multiple ISPs are involved in agreements with other remote ISPs. “You then have to worry about the partners maintaining the same level of quality. You have to somehow say that ‘this is the SLA for everyone in this area—you step out of that area, and you are on your own,’ ” says Stevenson.

“We need regulators to look in detail at IP interconnect. Until regulators tell ISPs that there needs to be a standard interface, there isn’t pressure for the technology to develop,” Stevenson says. This will change, he believes, as IP evolves from the minority to the infrastructure of choice. The European Commission is taking a look at the need for regulation in IP, so that carriers develop interconnect standards for IP service. “It might be best for regulators to step in, as most of the focus in IP regulation has been on voice,” Stevenson says. “The issues are not well understood. I suspect the European Commission will realize there is a problem, as they will see stark differences among EU countries. … Some of the Scandinavian countries have a free-wheeling attitude, while others, like France and Germany, have lagged behind in some respects.”

Though no decisions have been reached regarding QoS, the GSM Alliance recently opened a new category of associate membership, allowing GRX carriers to join to help operators and clearinghouses with GRX developments.

“We have set up a GRX/Operator Task Force to address issues such as QoS,” GSMA’s Hoffman says. He believes SLAs between operators and GRX carriers will address such issues, but concedes, “It may be some time before global QoS may be raised above ‘best-effort’ levels.”

Once QoS has been brought into the market, the TAP3 billing standard will be able to bill for such things as delay or level of service in a roaming environment.

How operators charge for roaming will ultimately depend on the ensuing definitions of QoS. For the time being, operators continue to charge a monthly flat fee, with a certain traffic threshold. Others may go further and add a per-kilobyte charge.

“We assume billing for QoS will not be quite as difficult as actually reaching agreement as to what QoS really is,” Hoffman muses. “We do expect that GRX carriers will interconnect with each other in order to provide one-stop shopping and traffic transport.”